Vulnerability Note VU#512705

The Alert Standard Format (ASF) Specification is a protocol developed by Distributed Management Task Force, Inc. (DMTF) that defines remote control and alerting interfaces for systems and devices when a host operating system is not present. The management firmware supplied with certain Broadcom NetXtreme network adapters supports ASF. A buffer overflow vulnerability exists in certain versions of this firmware when handling malformed ASF version 2.0 RAKP Message 1 packets. Devices with affected versions of the firmware would only be vulnerable if Remote Management and Control Protocol (RMCP) over the RMCP Security-Extensions Protocol (RSP) manageability is enabled. This functionality is typically disabled by default.

Broadcom identifies the affected devices and the latest vulnerable management firmware versions as

• BCM5751, BCM5752, BCM5753, BCM5754, BCM5755, BCM5756, BCM5764, BCM5787: v8.04
• BCM57760: v8.07
• BCM5761: v1.24.0.9

A remote, unauthenticated attacker may be able to execute arbitrary or chosen code on the embedded management controller or cause the controller to halt operation, resulting in a denial of service.

Apply an update from the vendor
Broadcom has released updated versions of the management firmware for all affected devices to PC OEMs as part of the Broadcom NetXtreme 14.0 software release. Users should consult the Systems Affected section of this document for information about specific OEM vendors.

Disable ASF support

Administrators can disable the management firmware or Secure ASF (RSP) support in the network interface management software.

Block or restrict network access

Blocking access to the ports used by the affected component (623/udp and 664/udp) from outside your network perimeter can help limit your exposure to attacks. However, blocking at the network perimeter would still allow attackers within the perimeter of your network to exploit the vulnerability.